@farmor
How did you previously depreciate property over 40 years, as you can see it is difficult to do in Turbotax.
US commercial property is depreciated over 39 years, except residential rental, which is 27.5 years.
If you previously depreciated commercial property over 40 years using another tax software or doing it yourself, then just let Turbotax do 39 years, it's not worth the effort to fix.
If you previously depreciated residential rental over a 40 year schedule (using another tax software or doing it yourself) the only way to fix that is to file a form 3115 with the IRS, that form is not supported by Turbotax and usually requires a CPA to complete since it is so complicated.
I don;t believe you can voluntarily choose 40 years instead of 27.5 years, I think you have to fix your old mistake.
